The concept of smoke-actuated door control has become a proven technique required today by most of the nation's model building codes. These codes specify that the control must be applicable to the doors which may be left open occasionally or at all times; because in many instances it is desirable both to hold a door in an open position to permit adequate air flow or free flow of traffic. The prior art is prolific in electrically-actuated door holder and release devices. Many of these devices include an electrically actuated control which releases the hold-open mechanism. Devices of this type are shown, for example, in U.S. Pat. Nos. 3,164,404; 3,415,562; 3,729,770; 3,796,451; and 3,926,461.